Signal path selection

[tmd_63]

I want to be able to select the signal in a stereo path. It is possible to simply provide a signal selection process using DSP or FFT methods?
I want to have a stereo signal (say an orchestra playing a composition) and be able to input the left and right channels into a processor when I can then select the spacial setting to select say the first violin from the whole orchestra. This would have a timing delay between the left and right channels due to the signal path of where the signal distance paths and volumes are different (the opposite of a pan control).
The system would have a signal position variable control to select anywhere in the entire panned area from extreme left to extreme right.
I know this would be a very difficult system to produce as it has to differentiate between different timing delays and volumes at the same time to select the correct signal source.

 

[andre_luis]

It seems an interesting application, but I would say that in a general way it may not be possible, because the sound intensity could vary according to the geometry of the show room, which implies the need of a pre-calibration of the system for just that musical instrument of the orchestra, separately. Also, this would have to be done for each song, in shorts, this can be quite complicated.

 

[KlausST]

Hi,

It´s not clear what you want to do.

Therefore I have to assume:
* Signal input = mono, digital (from microphone first violine)
* Signal output = stereo, digital
* Input: Panorama information: Digital? analog?

--> FFT is not related to this

--> DSP, if you want to do digital audio processing

Spatial setup:
Often one uses the simple volume control method.
But is is enormously more effective to add the timing dely.

I´ve around played with exactely this with an AnalogDevices DSP eval kit: EVAL-ADAU1701MINIZ
It was quite impressive: volume control works, delay control works, but both combined results in a far more precise audible location.

***
After re-reading your post....
maybe you want to filter single signal sources (violine) from an already stereo signal.
Here I doubt to get very good results, because the mixture of many signal sources and combined with echoes makes it extremely difficult to differentiat single signal sources.
The human ears do a very good job in this.

Klaus

 

[tmd_63]

OK.
A different scenario but the same implementation.
The device would have 2 mono inputs from microphones spaced at either side of the stage or a metal block. The device would have a mono output and the a variable control (or 2) that would allow the user to select where on the stage an instrument is or where inside the metal block a noise is and the output allows the user to listen to that individual sound source.
The device would not need to be extremely accurate, as the human ear and brain can assist in isolating the sound, but must be able to go a long way into isolating the sound.
For example, a stereo recording of 4 singers placed on a stage, they cannot occupy the same space on the stage so you can hear each singer on the stereo headphones, but this device would reduce 3 singers whilst enhancing any singer you select to isolate their singing from the others.